Growth factors, apoptotic cells and barx1 gene in bone and soft tissue of skeletal class III patients

Growth factors and growth stimulating genes are main signaling molecules for growth and development in ante- and postnatal period involved in cellular proliferation, differentiation and morphogenesis of tissues and organs during embryogenesis, postnatal growth and adulthood. The aim of this study was to evaluate TGF-beta (transforming growth factor-beta), BMP2/4 (bone morphogenetic protein 2/4), FGFR1 (fibroblast growth factor receptor one), barx1 gene and apoptosis from tissue samples of oro-maxillo-facial region in skeletal class III patients to reveal possible morphopathogenesis of severe skeletal anomalies. The study group included 9 patients with skeletal class III malocclusion. During orthognatic surgery tissue samples from tuber maxillae, ramus mandibulae anterior and posterior part, as well as gingiva from the lower jaw in region of second molar have been taken. Samples were stained with immunohistochemistry for TGF-beta, BMP2/4, FGFR1, apoptosis and barx1 gene. We used also the routine histological staining with haematoxyline and eosine. In tuber maxillae, ramus mandibulae anterior and posterior part staining for TGF-beta was the most relevant. Also BMP2/4, FGFR1 and barx1 showed the highest mean number of positive cells in tuber maxillae. Barx1 was equally expressed in ramus mandibulae, but BMP2/4 and FGFR1 mainly stained its posterior part cells. Apoptosis mostly affected ramus mandibulae anterior part. CONCLUSIONS: We suggest about more active stimulation of bone growth in tuber maxilla whereas ramus mandibulae. Apoptosis mainly affects ramus mandibulae anterior part that possibly connects to the lower expression of growth stimulating factors and may indicate lower bone remodelation ability.